Im not sure what's wrong :/ ?

So, I always used to over achieve when it came to school. I was one of those kids that teachers really liked. i could think out side of the box, problem solve and stuff and i used to get really good marks. Hell, I got one of the highest marks (93) in grade 11 forces of nature when i took it in grade 10, last year and i also got the highest mark (97) in grade 11 computer science ( took that in grade 10 as well ) . Now im in grade 11, and everything is awful. Im doing really bad in math, im at a 76, im doing well in physics but my physics teacher said that i won't cut it for grade 12 physics and I don't know what's wrong. It s like i lost that ability to problem solve and think out side of the box and stuff ( I just changed schools this year i went from a public school to a catholic school.. but it doesn't feel much different). And I don't know. I have so many nights filled with crying cause i can't get my marks as high enough as i used to and it hurts when i see other people getting through problems in math that i can't get through :/ I don't know what's wrong but i want this to stop :(